3,382 research outputs found
Composite fermions close to the one-half filling of the lowest Landau level revisited
By strictly adhering to the microscopic theory of composite fermions for the
Landau-level filling fractions nu_e = p/(2 p + 1), we reproduce, with
remarkable accuracy, the surface-acoustic-wave (SAW)-based experimental results
by Willett and co-workers concerning two-dimensional electron systems with nu_e
close to 1/2. Our results imply that the electron band mass m_b, as distinct
from the composite fermion mass m_*, must undergo a substantial increase under
the conditions corresponding to nu_e approximately equal to 1/2. In view of the
relatively low aerial electronic densities n_e to which the underlying SAW
experiments correspond, our finding conforms with the experimental results by
Shashkin et al. [Phys. Rev. B 66, 073303 (2002)], concerning two-dimensional
electrons in silicon, that signal sharp increase in m_b for n_e decreasing
below approximately 2 x 10^{11} cm^{-2}. We further establish that a finite
mean-free path l_0 is essential for the observed linearity of the longitudinal
conductivity sigma_{xx}(q) as deduced from the SAW velocity shifts.Comment: 5 pages, 2 postscript figure
Simultaneous Optimization of Block Replacement and Spare Part Ordering TIME for a Multi Component System with Separate Spare Part Ordering for Block and Failure Replacements
A block replacement schedule can be optimized simultaneously with a spare parts ordering schedule, since all items are replaced at a constant interval. The solution of joint optimization for spare parts ordering time and block replacement gives lower costs compared to separate optimization of ordering time and replacement time. The spare parts for replacement can be classified as stochastic demand for failure replacement and deterministic demand for block replacement. In this paper, we propose a simulation model for a separate spare parts ordering schedule. The solution was compared to the solution for a model with common spare parts for both failure and block replacement. The system has N identical components, each with a Weibull lifetime distribution. The costs of failure and block replacements, and also the costs of ordering, holding and shortage of spare parts are given. The proposed model was shown to perform better than the common order model. Also, compared to the age replacement model, the solution of the proposed model is relatively similar, yet the economies of scale would be an advantage for the block replacement over age replacement
Kebersihan Diri dan Sanitasi Rumah pada Anak Balita dengan Kecacingan
In Indonesia, helminthiasis is still a public health problem due to its prevalence. The prevalence is 45% - 65%. The species of helminthes whom infecting children under 12 years old are Ascaris lumbricoides, Trichuris trichiura, Ancylostoma duodenale, Necator americanus, and Enterobius vermicularis. It suspected that infestation of helmint can transmit through lack of environment sanitation and personal hygiene. The objective of research was analyze an association between housing environmental and helminthiasis among students of early childhood age. This research conducted since March until May 2010 with case control design and sample size was 51 subjectsfor cases and 51 subjects for control. Data analysis used chi square test and logistic regression. The prevalence of helminthiasis with feces examination among the students was 9,8%. The factors associated with helminthiasis were presence of latrines (OR = 5,245), defecation habits (OR = 4,821), type of floor (OR = 5,342), washing hands after defecation (OR = 4,654), and parental knowledge (OR = 2,425). It\u27s appleated to provide a close with good standard of environmental health, making the cement floor, increase knowledge about helminthiasis and the risk factor
Penerapan Akuntansi Pertanggung Jawaban sebagai Alat Penilaian Kinerja (Studi di Bagian Produksi PT. Pal Surabaya-Divisi Kapal Perang)
Each company founded by one or a group of people basically aims to improve customer satisfaction. If customers feel satisfied, then the profit can be obtained automatically. To achieve this goal, management must make decisions quickly and appropriately. This situation requires top management to delegate authority along with a control system, supervision and performance assessment manager underneath. This can be achieved by applying the accounting liability.Battleship Division PT. PAL, the author has not seen the application of accounting responsibilities. Therefore, the authors try to discuss and interpret existing data on the production by comparing the realization of financing and budget irregularities known to have occurred. Through the accountability report of the Outfitting Department, Ministry of Construction and the Ministry of Production Support, management can measure the effective and efficient production costs in the company. Thus, the company will have no difficulty in determining which of many costs that would affect the decision-making and increase overall company performance
Many-body diagrammatic expansion in a Kohn-Sham basis: implications for Time-Dependent Density Functional Theory of excited states
We formulate diagrammatic rules for many-body perturbation theory which uses
Kohn-Sham (KS) Green's functions as basic propagators. The diagram technique
allows to study the properties of the dynamic nonlocal exchange-correlation
(xc) kernel . We show that the spatial non-locality of is
strongly frequency-dependent. In particular, in extended systems the
non-locality range diverges at the excitation energies. This divergency is
related to the discontinuity of the xc potential.Comment: 4 RevTeX pages including 3 eps figures, submitted to Phys. Rev. Lett;
revised version with new reference
Analisis Pemberhentian Penyaluran Zakat Produktif Bergulir Di Baitul Mal
This study aims to determine the background or consideration of the distribution of revolving productive zakat in the form of machine and boat rickshaws and to analyze the causes of the dismissal of revolving productive zakat transfers in the Baitul Mal City of Banda Aceh. This type of qualitative research, data validity techniques using triangulation method, then using descriptive analysis. As for the background or consideration of the distribution of productive zakat in the form of machine rickshaws, that is first, the machine rickshaw is one of the transportation needed by the community after the tsunami, secondly, mustahik requires a lot of machine rickshaws to run its business and thirdly, the becak driver is easily run by mustahik. Then the distribution of aid in the form of a boat to help mustahik who live in coastal areas and work in the ocean. The cause of the dismissal of productive zakat distribution is first, problematic financing or bad financing. Second, the distribution of productive zakat in the form of a pedicab is stopped to avoid traffic congestion
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